The present invention relates to a technology of issuing an alarm according to the state of a controlled apparatus, particularly to an apparatus supervisory system suitable for application to a blood pump system for an artificial heart by which the state of the blood pump and the state of a controller for the blood pump are supervised and an alarm is issued as required.
An artificial heart has hitherto been adopted as an apparatus capable of substituting for the function of a heart. An artificial heart is composed mainly of a blood pump for circulating the blood and a controller for controlling the operation of the blood pump. Upon an abnormal state generated in the operation of the blood pump, the controller functions as alarm generating means for generating an alarm to inform the user of the abnormal state.
Since the blood pump of the artificial heart supports the human life directly, a failure of the alarm generating means may possibly be fatal. In view of this, it has been practiced, as a measure for coping with a failure of the alarm generating means,
(1) to confirm the absence of a failure by issuing an alarm sound for confirmation either periodically (in a scheduled manner) or non-periodically (in a nonscheduled manner), and
(2) to duplex the alarm generating means.
For example, Japanese Patent Laid-Open No. 2005-434 (corresponding to U.S. Patent No. 2005014991 A1) discloses a technology for informing the user of an abnormal state of a blood pump and an abnormal state of a controller for the blood pump, by use of an LED or a buzzer.